Fluid-pressure regulator for automatic brakes



G; WBSTINGHOUSEJ1 A VFlu-id mPressure Regulator for Automatic Brakes.

4`|\1 o."24o,o62.7 Patented April 12,1881`-`4 UNITED l NSTAT-Es PATENT OFFICEG GEORGE WESTINGHOUSE, JR., OF PITTSBURG, PENNSYLVANIA.

FLUID-PRESSURE REGULATOR FOR AUTOMATIC BRAKES.

SPECIFICATION forming part `0f Letters Patent N0. 240,062, dated April I2, 1881.

` Application filed March 9, 1881." (No model.) i

To all whom it may concern.-

Be it known that I, GEORGE WEsTING- HOUSE, J r., of Pittsburg, county of Allegheny, State of Pennsylvania., have invented or discovered a new`and useful Improvement in Fluid- Pressure Regulators for Automatic Brakes; and I do hereby declare thefollowing to be a full, clear, concise, and exact description thereof, reference being had to the accompztnying drawings, making a part otlthis speciiication, in which-like letters indicating like parts- Figure 1 is a vertical sectional view of my improved regulating device 5 and Fig. 2, by a diagram view of the main operative parts of an air-brake apparatus, illustrates the manner of its use.

In the construction and use of duid-pressure brake apparatus it is exceedingly desirable that a uniform working-pressure bemaintained at all times, as near as may be. `Usually heretofore the engineer has had to rely on observing his pressure-gage for this purpose, and has had to start or stop his pump accordingly. It is highly desirable that the engineer be relieved from this care, especially as variations in working-pressure are liable to be greatest at times or in emergencies when his attention is required for other duties.

My present invention relates to` regulating the speed and action of the pump automatically by variations in the working fluid-pressure which is stored up for use in operating the brakes, and as the principal use I propose praetically to make of the invention is as a part of the Westinghouse automatic-brake apparatus l will first explain such use.

R, Fig. 2, indicates the main reservoir, and P the pump. The air-supply to the pumpingcylinder is represented at p, and the dischargepipe leading to the main reservoir at p. The ordinary operating-cock is shown at q, and the usualpipe-connections g g2 are .made from it to the main reservoir and to the brake-pipe g3, which passes 'back beneath the cars with the usual hose and couplings between the cars. Beneath and connected with each ear is an auxiliary reservoir, R', brake-cylinder O, and triple valve R2, with the usual pipe-connections. These all have the construction and operation well known in the art.

My improved regulating device B has a pipeconnection, b', leading from the boiler and opening into the regulator at port B. From the opposite port, B2, a pipe, b2, leads toV the pumping-engine, and a third pipe, b3, leading from the brake-pipe q2 or g3 at any desired point back of the cock q, leads to a third port, B3. The regulator B has a double-ported U- shaped diaphragm, a, in the ports' of which are seated the valves a a2, which together constitute a balanced valve. Both valves are on the same stem, and they are guided in their motionin Vany suitable way, as by a winged stem below and a straight` stem playing ina socket above, as shown. A comparatively light spring, a3, is arranged to press the valves to or toward .their seat.

y In a chamber. made about midway between the ends of the regulator I arrange a packed piston, D, and on its stem D', I arrange a com- 7o parativelystift or heavy spring, d, in such manner that its tendency will be to force the piston upward. While the lower end of the piston-stem is `closed the remainder is hollow, and in the cavity is fitted a bushing, d', suitable for guiding a stem, d2,one end ot which rests against the bottom of the piston-stein cavity, and the other end bears against the lower end of the valve-stem, so that as the piston Dgoes down under the action of an ex- 8o cessive air-pressure applied to its upper end, as presently to be described, `the valves will be free to be seated, either by their own weight or by the action of the spring a3, which is to be made strong enough for the purpose, and such seating of the valve will cut off the iiow -of steam from the boiler to the pumping-engine, andas such excessive pressure is relieved, so that the spring d (made suciently heavy for the purpose) shall cause the. piston to rise, the valves will be unseated and steam will be admitted through the pipe b', port lB', valve-ports, port B2, and pipe b2, to the engine-pump, to start it in operation.

In order thatthe excessive pressure inthe 95 brake-pipes (when it exists) may be brought to act on the end ofthe piston D, I provide in the lower part of the regulator aflexible diaphragm, g, arranged in a chamber, Gr, and properly secured at its edges to the case and at its center to a stem, g. v

Beneath the diaphragm and pressing up- ICO ward I arrange a spring, g2, and by means of' a screw-nut, g3, I soregulate the resiliency or liftin g-power of the spring that in its normal condition, and as against the desired working airpressure, it will press the diaphragm up, and thereby hold to or nearly to its seat a valve, o, which is secured to the upper side of' the diaphragm, and-which opens and closes a line of' ports, s s s2 s3, which leads to the chamber s4 above the piston D.

From the port B3, which by the pipe b3 is in communication with the brake-pipe, a line of' ports, c c c2 c3, leads to the diaphragm-chamber i G above the diaphragm.

In the usual or norlnal condition of the apparatus the valves a a will be slightly open, so as to let enough steam through to run the pump fast enough to keep up an ordinary working-pressure of, say, seventy pounds per square inch, more or less, as against loss by leakage. If, for any reason, the pump should operate so fast as to run up the air-pressure above that indicated,the excess of pressure, acti n g through the pipe B3 and ports c c o2 c3, will depress the diaphragm g more or less, according to the amount of' such excess, open the valve t, and then the pressure following ports and vpassages s, s', s2, ands3 will become operative in s4 on the piston D, with the resultof depressing it, and thereby leaving the valves a a free to come to their seats under the action of' the spring a3. The steam will then be cut off and tbc pump will stop. As soon as, by leakage or by the lowering of air-pressure in the brake-pipes, (done for the purpose of appying the.brakes,) the air-pressure in the brake-pipe falls below normal working-pressure a consequent reduction of pressure takes place in chambers 4s4 and G, as a'result of' which the valve o is seated, and the spring d raises the piston D, and, acting through the stem d2, lifts the valves a a', and lets steam onto the pump, so as to start it again in action. If the valve o should be thus seated before the pressure in s4 is sufficiently reduced, ordinary waste by leakage will speedily reduce it to the desired extent. Hence the action or non-action of the pump depends on variation of air-pressure in the brake apparatus above or below normal pressure, so that a practically constant air-pressure will be preserved by the automatic action of the apparatuswithout requiring the constant care of the engineer, l

In order to guard against the effects of leakage of fluid-pressure to parts of the regulator where its presence is not desirable, I provide leakage-ports n a', as may be required.

The ports s2 and c are by preference made annular, and extend entirely around the case, in order that, as the parts composing the case are screwed together, the ports s and s3, as also the ports c and c, may be in communication, even if in screwing the parts of the caseA together such ports do not come into line with each other.

The same regulator may be employed as a part of' a non-automatic fluid-pressure brake by connecting the pipe b3 with the main reser- Vo-ir, as illustrated by dotted lines z, Fig. 2, instead of with the brake-pipe; and the like connection with the main reservoir may be made even in the automatic brake, if so preferred, though less advantageously.

As one part of the novelty of the present apparatus consists in combining with a throttle or shut-off valve and a diaphragm and valve a piston subject to duid-pressure on one side and a spring-pressure on the other, I include herein as of my invention suchl combination as herein shown, and all modifications thereof, with or without additions thereto, such as involve substantially a like operation, and particularly such modification as would adapt it for use as an element in` the construction -and operation of' steam-engine governor-valves and air-compressing apparatus generally.

I claim herein as my inventionl. A piston subject to duid-pressure on one side and a spring-pressure on the other, in

combination with a throttle or shut-O1 valve arranged to open and close/the steam-dow io the engine, and a diaphragm and valve arranged to regulate the admission of duid-pressure to the piston, substantially as set forth.

2. In combination with a fluid-pressure geu-Y erator, auxiliary reservoir, and brake-cylinder of an automatic brake apparatus, a regulatingpiston, throttle, diaphragm, and valve, arranged for conjoint action, substantially as set forth.

3. In combination with piston D, actuated by variations in fluid-pressure applied thereto, a balanced valve, a a', actuated therefrom, and a diaphragm-valve, o, arranged to open and close the port through which air-pressure is admitted to the piston, substantially as set forth.

4. In combination with the continuouslycharged pipe or reservoir of' a fluidpressure brake apparatus, a line of pipes and ports leading to one side of a movable diaphragm and thence to a piston-chamber, the piston whereof actuates the throttle or shut-off' valve, a valve, o, arranged in such line of ports for opening and closing the same from the diaphragm motion, and a spring, g2, for moving the diaphragm on the diminution of air-pressure, substantially as set forth.

In testimony whereof I have hereunto set my hand.

GEORGE WESTINGHOUSE, JR-

Witnesses:

R. H. WHITTLEsEY, GEORGE H. CHRIsTY.

IOO 

